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61.
Cytokines have a central role in multiple sclerosis (MS) pathogenesis and may contribute to the aetiology of MS. A polymorphism in the IFNA17 gene with an allele carrying a pre-mature stop codon has been suggested to convey a 26-fold increased risk for MS. We investigated the possible association between this polymorphism and MS using population-based samples from a genetically well-characterized population. The IFNA17 gene variant was found in 2.8% of 327 MS cases and 3.3% of 698 referents ( P = 0.64). Thus, our study does not support an association between the IFNA17 allele and risk for MS. 相似文献
62.
纤溶酶原激活剂抑制物-1及其基因多态性与急性心肌梗死的相关性研究 总被引:2,自引:0,他引:2
目的:研究纤溶酶原激活剂抑制物-1(PAI-1)活性及其等位基因多态性与急性心肌梗死(AMI)之间的关系,从基因水平揭示AMI发病的危险因素。方法:AMI组55例、对照组48例健康者分别应用特异性寡核苷酸点膜杂交技术,进行PAI-1启动子区4G/5G多态性分析,用发色底物法测定血浆PAI-1活性。结果:AMI组和对照组中4G/4G基因型的血浆PAI-1活性水平最高,与4G/5G基因型、5G/5G基因型比较有显著性差异(P<0.01)。AMI组中4G/4G纯合子基因型频率明显高于对照组(P<0.05)。结论:血浆PAI-1活性增高是AMI发病的危险因素之一,4G/4G纯合子基因型是AMI发病的危险基因型。 相似文献
63.
Polymorphism analysis of four canine MHC class I genes 总被引:1,自引:0,他引:1
Abstract: We have studied the variability of four structurally complete dog leukocyte antigen (DLA) class I genes, termed DLA-12, -88, -79 and -64, in a population of mixed breed, unrelated dogs. The human HLA and canine DLA loci share a high degree of similarity in terms of gene structure. This analysis focused on the first three exons of each of four complete canine genes. Exons two and three are the major source of polymorphism in the corresponding human genes. In this analysis, DLA-88 was found to be significantly more polymorphic than the other three genes, with 44 distinct alleles observed among 63 mixed breed, unrelated dogs. The remaining genes had between one and four alleles when examined in 25 dogs. This work was carried out as part of an effort to develop an MHC typing system for the dog, which is critical to the further development of preclinical studies of hematopoietic stem cell and solid organ transplantation in the canine model. 相似文献
64.
Clinical and diagnostic DNA laboratories must maintain a large inventory of DNA probes for use in hybridization studies. The preparation of plasmid DNA and isolation of DNA fragments for use as probes in both expensive and time consuming. We present here a rapid and relatively inexpensive method of producing large amounts of DNA fragments from stocks, using the polymerase chain reaction (PCR). Our experience over the past year using this technique has been very positive and we believe many laboratories could benefit by employing such a labor-saving approach to maintaining DNA probes. The technique uses the bacteriophage M13 DNA sequencing primers to amplify cloned inserts contained in commonly used plasmid vectors. As examples, we illustrate the use of DNA produced in this manner as probes for linkage analysis of the fragile X syndrome and for detection of deletions in the Duchenne muscular dystrophy gene. We have also found that at least two probes can be amplified in the same PCR reaction, allowing the detection of two different restriction fragment length polymorphisms (RFLP) simultaneously. It should be possible for laboratories to devise strategies particular to their individual needs using more than one DNA probe produced in the same PCR reaction to detect RFLP's. Such strategies would need only to consider that the predicted alleles of the multiple polymorphisms do not migrate to the same position during electrophoresis. Stocks of single or multiple probes produced by the PCR could then be maintained for more rapid Southern analyses. 相似文献
65.
毛细管电泳技术快速检测p53基因点突变 总被引:1,自引:0,他引:1
目的:探讨利用毛细管电泳技术快速检测p53基因点突变的临床应用价值。方法:采用毛细管电泳作SSCP分析,检测20例结肠癌肿瘤标本p53基因第7外显子PCR扩增产物,并与传统的聚丙烯酰胺凝胶电泳结果进行比较,最后用DNA序列测定判断其准确性。结果:20例结肠癌标本中,毛细管电泳技术检测出5例标本(Ca4,Ca6,Ca7,Ca8,Ca14)有突变,而凝胶电泳结合银染技术仅检出4例标本(Ca4,Ca6,Ca7,Cal4)有突变,测序证实经毛细管电泳所检出的5例标本均存在点突变。结论:对于PCR产物的单链构象多态性分析,毛细管电泳技术是一种更加快速、简便、敏感的方法,可应用于临床筛查基因点突变。 相似文献
66.
北方汉族人群维生素D受体基因Bsm I位点多态性与前列腺癌易感性的相关性分析 总被引:1,自引:1,他引:0
目的 :研究低发病的中国汉族人群维生素D受体基因 (VDRG)BsmⅠ 位点单核苷酸多态性 (SNP)与前列腺癌的关系 ,探讨不同种族前列腺癌发病的基因差异。 方法 :收集中国北方地区汉族人群 10 3例前列腺癌病人及10 6例健康对照者外周血标本 ,应用变性高效液相色谱 (DHPLC)检测VDRG第 8内含子BsmⅠ多态位点 ,并对该位点SNP分布进行分析。 结果 :BsmⅠ 多态位点bb、Bb、BB基因型和等位基因在北方地区汉族前列腺癌病人及对照者中的分布频率差异无显著性 (P >0 .0 5 ) ,基因型分布频率分别为 92 .2 3%、7.77%、0和 94.34 %、5 .6 6 %、0 ;等位基因B、b分别为 3.88%、96 .12 %和 2 .91%、97.0 9%,而与高发病人群的分布相比有显著不同。 结论 :VDRGBsmⅠ多态性在低发病的中国汉族人群与前列腺癌无相关 ,其分布与高发病人群有明显差异 ,提示VDRGBsmⅠ多态性可能是前列腺癌发病种族差异的原因之一。 相似文献
67.
Hemophilia A: genetic prediction and linkage studies in all available families in Finland 总被引:1,自引:0,他引:1
Anna-Elina Lehesjoki Pertti Sistonen Vesa Rasi Albert de la Chapelle 《Clinical genetics》1991,39(3):199-209
RFLP studies were done in 82 (75%) of all known hemophilia A families in the Finnish population (approximately 5 million). Two intragenic RFLPs (Bc1I/F8A, XbaI/p482.6) and two extragenic markers (TaqI/St14, Bg1II/DX13) were used. Among 263 females at risk, carriership could be evaluated with an intragenic marker in 47% and with an extragenic marker in 26%. In 27% of the females, carriership could be neither excluded nor confirmed; 68% of these females were relatives of an isolated patient. Eight recombinations between the factor VIII gene (F8C) and DXS52 (lod 25.02 at theta max 0.06), eight recombinations between F8C and DXS15 (lod 21.91 at theta max 0.05), and two recombinations between DXS52 and DXS15 (lod 33.56 at theta max 0.01) were found. Using multipoint linkage analysis, the most likely order of loci supported by the data was: F8C-DXS15-DXS52-DXS134. RFLP segregation analysis provides a highly useful method of carrier detection and prenatal diagnosis of hemophilia A, but its limitations must be carefully taken into account. 相似文献
68.
目的探讨广东地区宫颈癌组织中HPV16肿瘤相关性抗原E7基因序列的多态性.方法采用通用引物PCR直接测序法对宫颈癌标本中的HPV分型,从含有HPV16型的标本中采用自行设计的多重引物通过巢式PCR扩增出HPV16E7,经DNA序列测定法检测其基因变异,进而寻找其热点突变.结果50例宫颈癌组织HPV-DNA的检出率为78%,其中HPV16和HPV18型混合感染18例,单纯HPV16型感染15例.33例含有HPV16型的标本中扩增出25例HPV16E7,其中17例647位核苷酸“T”变异“C”,导致相应的蛋白质由天冬氨酸变异为丝氨酸.结论广东地区宫颈癌组织中HPV16E7DNA序列发生碱基替换的区域主要在647位至846位,热点突变点为Nt647和Nt846. 相似文献
69.
K. Kawabe K. Goto I. Nishino C. Angelini Y. K. Hayashi 《European journal of neurology》2004,11(10):657-661
Mutations in the dysferlin gene (DYSF) on chromosome 2p13 cause distinct phenotypes of muscular dystrophy: limb-girdle muscular dystrophy type 2B (LGMD2B), Miyoshi myopathy (MM), and distal anterior compartment myopathy, which are known by the term 'dysferlinopathy'. We performed mutation analyses of DYSF in 14 Italian patients from 10 unrelated families with a deficiency of dysferlin protein below 20% of the value in normal controls by immunoblotting analysis. We identified 11 different mutations, including eight missense and three deletion mutations. Nine of them were novel mutations. We also identified a unique 6-bp insertion polymorphism within the coding region of DYSF in 15% of Italian population, which was not observed in East Asian populations. The correlation between clinical phenotype and the gene mutations was unclear, which suggested the role of additional genetic and epigenetic factors in modifying clinical symptoms. 相似文献
70.
目的 :观察雅施达 (培哚普利 )治疗老年人充血性心力衰竭 (CHF)的临床疗效。方法 :5 9例经常规洋地黄、利尿剂、血管扩张药等治疗效果欠佳的CHF老年患者 ,给予口服雅施达 2mg/d4mg/d ,治疗 4周 6周。观察治疗前后心率、心胸比、血压、左室舒张末期内径、左室射血分数以及心功能变化。结果 :治疗后心率、血压、心胸比以及左室舒张末期内径与治疗前比较均明显下降 (P <0 .0 5 )。左室射血分数增加 (P <0 .0 5 ) ,心功能改善 1级 2级。药物副作用少 ,患者耐受性好。结论 :雅施达治疗老年人CHF疗效好 ,副作用少 ,是理想的治疗药物 相似文献